You can crimp on new connectors but it takes a special tool to handle the size. I replaced the positive battery connection and it was pretty difficult to crimp without a tool. I ended up soldering the connection by pre tinning the wire and the connector and then put them together and then added additional solder using a propane torch. It takes a lot of heat to prevent a cold solder joint.
Cold solder joint or a improper crimp is going to cause a voltage drop.